Antiperspirant products are well known in the art. Antiperspirants have appeared in the marketplace in varied dosage forms, such as sticks, soft solids, soft gels, roll-on, aerosols and creams. Generally, these dosage forms include a solution of the active ingredient in a suitable solvent, a suspension of the active ingredient in a non-solvent, or a multiphasic dispersion or emulsion in which a solution of the active ingredient is dispersed in some continuous phase or in which the solubilized active ingredient constitutes a continuous phase.
Of the above-referred-to dosage forms, the stick form is an example of a solid form, and the soft solid and soft gel are thickened forms which may or may not be solid (for example, under some circumstances, gels can flow). The stick form can be distinguished from a soft solid or soft gel in that, in a stick, the formulated product can retain its shape for extended time periods outside the package, the product not losing its shape significantly (allowing for some shrinkage due to solvent evaporation). Adjustment of amounts of gelling or thickening agents can be used in order to form a soft gel or stick.
Soft gels or soft solids can be suitably packaged in containers which have the appearance of a stick, but which dispense through apertures (for example, slots or pores) on the top surface of the package. The soft solid products have also been called soft sticks or “smooth-ons”, and hereinafter are generically called “soft solids”. Reference is made to U.S. Pat. No. 5,102,656 to Kasat, U.S. Pat. No. 5,069,897 to Orr, and U.S. Pat. No. 4,937,069 to Shin, each of which discloses such soft solids, including physical characteristics thereof such as viscosity and hardness. The contents of each of these three U.S. patents are incorporated herein by reference in their entirety for description of characteristics of soft solids and suitable packaging for such products.
Recently, there has been significant activity in developing clear antiperspirant sticks and soft gels, particularly to provide sticks and soft gels having increased efficacy (for example, by providing increased amounts of the antiperspirant active in the sticks and soft gels), improved cosmetic characteristics (including reduced whitening, reduced residue and reduced tack), and reduced skin irritation potential (e.g., providing a product that is “mild”).
U.S. Pat. No. 4,944,938 to Potini discloses clear, non-alcoholic, quick drying, antiperspirant and deodorant gels, which are stable both at room temperatures and at higher temperatures, are non-stinging and leave no white residue on the skin. The gel is free of gelling agents, waxes, clays, or monohydric alcohols having 2–8 carbon atoms. The gels use 3–5 carbon atom trihydric alcohols as coupling agents which act as solubilizers in the system and keep the system stable and clear. The gels can include an aluminum active salt; a volatile water-insoluble emollient, such as isostearyl benzoate: a soluble emollient such as cetyl ether; solubilizers such as propylene glycol and glycerin; volatile siloxanes; and water.
Some cellulosic materials, such as hydroxypropylcellulose, among others, are compatible with polyvalent metal salts and have been used in the manufacture of clear lotions. These cellulosic materials, however, must be prepared with a high percentage of water or alcohol in order to insure solubilization of the active ingredient. The resulting formulations, in addition to a high irritation potential, are tacky and low in efficacy, when alcohol-based; and exhibit tackiness and along drying time when water-based.
Clear antiperspirant soft gels (which have been dispensed from containers having the appearance of stick) have recently been marketed, consisting of viscous, high-internal-phase emulsions. These soft gels exhibit some advantages over the aforementioned sticks, particularly acetal-based clear sticks, in that the selection of formulation ingredients is less restricted (for example, water can be used), and often tack can be reduced significantly. Concerning these emulsions, note U.S. Pat. No. 4,673,570 to Soldati and U.S. Pat. No. 4,900,542 to Parrotta, et al. These two U.S. patents disclose clear gelled antiperspirant compositions free of waxes and conventional gelling agents, containing a volatile silicone fluid, a silicone emulsifier, a destabilizing auxiliary emulsifier, water, non-volatile emollient, a coupling agent, an active antiperspirant component and ancillary agents such as perfume, coloring agents, etc. The silicone emulsifiers a cyclomethicone-dimethicone copolyol silicone fluid marketed by Dow Corning Corporation under the trademark DOW CORNING 3225C formulation. In particular, U.S. Pat. No. 4,673,570 claim 1 is “from about 10–25% by weight of a cyclomethicone-dimethicone copolysilicone fluid (same as 1.0–2.5% on an actives basis). The contents of these two U.S. patents are incorporated herein by reference in their entirety with respect to the features of the inventions described therein.
Also to be noted is PCT (International application) Publication No. WO 92/05767. This patent document discloses a clear gel-type cosmetic product having a viscosity of at least about 50,000 cps at 21 degrees C. and a refractive index of 1.3975–1.4025 at 21 degrees C., and having an optical clarity better than 50 NTU (Nephelometric Turbidity Units) at 21 degrees C., the product being an emulsion with a water phase having an active ingredient incorporated therein and with an oil phase. The refractive indices (measured at 5893 Angstroms) of the water and oil phases match to within 0.0004. The oil phase includes an emulsifier which when properly mixed with the water phase component yields a water-in-oil emulsion, and the water phase includes one or a combination of various polar species such as water, propylene glycol, sorbitol and ethanol. The water phase includes the deodorant and/or antiperspirant active ingredient. The contents of this PCT (International application) Publication No. 92/05767 are incorporated herein by reference in their entirety.
U.S. Pat. No. 6,007,799, assigned to the same owner as this case, describes clear cosmetic gels that are water-in-oil emulsions and which comprise at least one coupling agent, silicone fluids and an alkoxylated, alkyl substituted silicone surface active agent.
U.S. Pat. Nos. 5,587,153 and 5,863,525 issued to Gillette also describe gel products that (1) contain silicone in the oil phase and (2) does not control the propylene glycol content.
U.S. Pat. No. 5,925,338 issued to Gillette describes a clear gel comprising selected amounts of various types of silicones.
U.S. Pat. No. 6,419,910 assigned to Unilever describes a clear emulsion and gel-type antiperspirant and deodorant composition which comprises a water in oil emulsion which is essentially free of glycols and low and middle chain alcohols. The composition comprises 25–35% of an oil phase comprising at least one non-volatile ester or at least one nonvolatile silicone wherein at least one oil phase soluble ingredients has a refractive index of about 1.40 to about 1.45. The active phase contains a water soluble, non-simple glycol component which raises the refractive index of the aqueous solution.
U.S. Pat. No. 6,410,002 and U.S. Patent Application 2002/10051138 A1 also assigned to Unilever, describes an essentially glycol free clear emulsion and gel-type antiperspirant and deodorant composition in which the water phase further differentiated by containing at least one polymeric ethylene oxide glycol and is essentially free of glycols and low and middle chain alcohols
U.S. Pat. No. 6,042,816 describes enhanced efficacy antiperspirant salt compositions containing calcium and an amino acid or a hydroxy acid, methods of making such enhanced efficacy antiperspirant salt compositions, stabilized aqueous solutions of such enhanced efficacy antiperspirant salt compositions, and topical compositions containing such enhanced efficacy antiperspirant salt compositions.
U.S. Pat. No. 6,468,512 assigned to Avon describes a clear antiperspirant/deodorant gel composition. The composition is a water-in-oil emulsion having a viscosity about 7,000 cps to about 25,000 cps and a clarity from about 30 NTU or less. The composition further has an antiperspirant active, water, silicone gelling agent, and one or more silicone oils.
U.S. Pat. No. 6,485,716 assigned to the same owner as the present case describes a clear, elastomer-free, gel composition comprising: (a) 0.1–25 weight % of an antiperspirant active having a low metal to chloride ratio in the range of 0.9–1.3:1; (b) 9–23.95 weight % of one or more volatile silicones having a flash point of 100 degrees C. or less; (c) 0.05–0.5 weight % of a silicone surfactant having an HLB value less than or equal to 8; (d) 30–70 weight % water; (e) 0–50 weight % selected water soluble organic solvents; and (f) 0–10 weight % of an emollient; wherein the composition is a liquid gel having a viscosity in the range of 5–50,000 centipoise and a ratio of oil phase to water phase in the range of 10:90 to 24:76.
U.S. Pat. No. 6,500,412 assigned to the same owner as this case describes a non-sticky, clear water-in-oil emulsion comprising: (a) 65–90 weight % of an internal phase comprising 5–35 weight % of an antiperspirant salt (anhydrous basis) having a metal:chloride ratio in the range of 0.9–1.4:1; 5–15 weight % of tripropylene glycol; and 35–70 weight % water; and (b) 10–35 weight % of an external phase comprising 1–40 weight % of a volatile silicone which is not an elastomer; 0.1–5 weight % of a silicone copolyol surfactant; and 0–20 weight % of a nonvolatile silicone which is not an elastomer; wherein the composition is free of (1) C1–5 saturated alcohols, (2) added propylene glycol, (3) elastomer gelling agents, (4) soap gelling agents (5) borate gelling agents, and (6) coupling agents, and wherein all amounts are in % by weight based on the total weight of the composition.
While various cosmetic gel compositions, including antiperspirant and deodorant compositions that are clear are known, it is still desired to provide a cosmetic gel composition (e.g., clear antiperspirant and/or deodorant gel composition) which has improved efficacy in comparison to other products, especially other commercially available gel products. It is a further object of the invention to provide products which have (a) reduced whitening, (b) low tack, (c) a quick dry down profile and (d) reduced skin irritation potential relative to commercially available products. It is yet another object of the invention to provide gel antiperspirant/deodorant products which are free of oil soluble high refractive index (>1.420) emollients (which tend to slow down drying time of the gel composition due to their low volatility). This invention has an oil phase which has a relatively low refractive index when compared to other clear gels, thereby reducing the level of water soluble organic or silicone based refractive index matching agents (such as glycols and other monohydric or polyhydric alcohols, ionizable monovalent or divalent inorganic salts, sugars, esters and amino acids) used to match the refractive index of the water (internal) phase to the oil (external) phase to obtain a clear gel.